Scourge of humanity to Last,Best hope of Humanity?

So i got to 20 as evil, and got the achievement Scourge of Humanity, and i decided to get a quick 5-6 achievements by going to rivet city and donating like 1500 caps to the church and bam i was "Last,Best hope of humanity in like 5 seconds... and i did not get any achievements... did i do something wrong?